i hooked up my k3 to a 3/8" air line (maybe smaller) @ 150psi, it had a 1" to 3/8" adapter on the manifold. the horns were very disappointing, not loud at all, is it just the small airline holding them back? i was looking at getting the single mounting solution and it only uses 3/8" line from the manifold to the horns with a 1" input on the manifold, i sure hope they will be louder than my outlaws…
First of all, these nathans need at LEAST a 1/2 in air line supplying the horn. Any smaller it will starve the horn. Second, does it have a restrictor in the bottom of the manifold? Where you plumb the airline into the manifold. Do you know if it is a “Over the Road” horn? If it is, it should have a allen like bolt that has a small diameter hole in the center of it. Take that out and you should have a LOUD horn. By all means though, get a larger air line.
thanks for the reply, thats what i thought
yes i use 1/2 air line an 1/2 valve and hell they are loud!
if they still sound not loud ill trade you a set of loud shockers for them… they’ll put outlaws to shame …lol;)
no thanks, just cleaned them up today:D… my buddy has a set of hb4h’s on his s-10, they sound better but are not louder. i use a 3/8 smc solenoid with 3/8 shop air line, its way louder than how they come
where in fl r u
Pensacola
Dude, give the horns what they want… 1/2" air supply… they will be louder…
there is a very big differance in sound when going between the two air hose sizes
I just doubled my volume going up to 1/2" ID rubber air hose which is larger (more air) than 1/2" nylon tube. The difference really shocked me and my ears are still ringing several hours later. See this post:
http://www.trainhornforums.com/showthread.php?p=29843#post29843
3/8 is way to small. to feed all the horns. Shop airline and the fittings are too restrictive. The horn is 1/3 as loud as it will be when having the correct volume to it.
My single brackets run from a 1/2 manifold inlet, to 3/8 inch output for each horn. Thats 3/8 inch to each horn, not all horns.
I more then double the volume needed for the horns.
I use 3/8 inch Airline for the Brackets and fittings. The stock Air inlet on the horns is 4 mm I.D. The Airline and fittings at there smallest point is 9mm I.D. What all that means is there is no worry of your horns being starved for air.
they’ll “infract” you for posting those images lol… like i had for posting images from your website 
Reason: Spammed Advertisements
You can’t send people to ***realtrainhorns.com , c-mon are you serious?
This infraction is worth 1 point(s) and may result in restricted access until it expires. Serious infractions will never expire.
Infracting me had me switch over to that particular website in the first place. I considered getting a K3 from HB.
btw i hadn’t even notice your website link in those images I posted since they were like 6 pts small.
looks more like 3mm to me. 
Good point, I should remove them.
INTERESTING POINT ON THE 2 AIRLINE SIZES . JUST INSTALLED MY K3s WITH 10 GALLONS OF AIR , ITS 1/2 INCH FROM THE TANK TO MY MANIFOLD , AND 3/8 FROM MANIFLOD TO HORNS , THE HORNS ARE AT DIFFERENT LOCATIONS . THE SOUND IS LOUD AND CRISP BUT ARE YOU TELLING ME THAT IF I HAVE 1/2 INCH TO THE HORNS THEN THEY LOUDER ? WHERE CAN I GET A SMALL 1/2 INCH OUT 3 PORT MANIFOLD THEN .
it also might be the valve you have if you didn’t get it from hb. i had a sad k3 for a while and replaced the valve with the snc nickel 1/2highflow valve and presto! 
again
GOT ALL MY KIT FROM THE FAB GARRETT AT HB . CAN YOU BELIEVE THAT I TOOK THE CASH TO HIM IN PERSON ? FLEW OVER FROM SCOTLAND , DROVE TO THE FAMOUS HOME OF HB HANDED HIM THE DOLLARS AND PRESTO THE K3s AND GOODIES ARRIVED IN THE POST . I HAD TEETHING PROBS WITH A PRESSURE SWITCH , IT WASNT GOOD ENOUGH TO HOLD THE CURRANT FROM ONE COMPRESSOR AND FAILED . SO TODAY I REPLACED IT AND TOOK ALL THE CURRANT AWAY FROM IT AND USED ANOTHER 70 AMP RELAY INSTEAD . NOW BOTH COMPS HAVE THERE OWN RELAYS AND ONLY 1/2 INCH AIR IS RUNNING THROUGH THE SWITCH . ALL IS WELL AND VERY LOUD . JUST A COUPLE OF WEE LEEKS TO FIX . THANKS FOR THE HELP . KEITH . PHOTOS ON THE WAY .
wait you flew in from scotland just for that?!? tell me that was on the way of something. if not, you must’ve wanted it bad haha. badder than i did
… and i feel like you’re yelling at me
